Conventional detection and identification procedures for mycobacteria require growing the organisms from patient specimens and then determining various phenotypic characteristics of the isolated organisms. These techniques may take from a minimum of several days to a month or more. Molecular methods offer the hope of drastically reducing these time periods, potentially allowing much more rapid diagnosis of mycobacterial infections. We have been working on methods to extract mycobacterial DNA directly from patient specimens (we have been using a freeze-boil technique) and then using the polymerase chain reaction (PCR) procedure to amplify a portion of the mycobacterial 165 rRNA gene. Work in this area has continued but now involves the use of different, newly-designed primers and another amplicon-detection mechanism. For details on that project, see project number Z01 CL-10279-01 CPD.